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Author Topic: Texture smoothness  (Read 2684 times)

cadm8

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Texture smoothness
« on: September 19, 2017, 12:12:49 PM »
Would anybody recommend a workflow for producing better looking texture, especially for high objects, like the quarry belts I'm attaching below? I'm looking to produce a more homogenous surface-texture, avoiding the vertical lines shown. Adaptive orthophoto method produces a better looking texture than generic, but still, the surface is not so clean looking
« Last Edit: September 19, 2017, 12:55:31 PM by cadm8 »

cadm8

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Re: Texture smoothness
« Reply #1 on: September 19, 2017, 12:56:13 PM »
Sorry forgot to add the attachment

SAV

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Re: Texture smoothness
« Reply #2 on: September 19, 2017, 01:09:31 PM »
Hi cadm8,

You will probably need to adjust your UAV image acquisition / survey design.
 
Collect oblique imagery (camera pointing down at about 65-75 degrees from horizontal) and fly a 'grid survey' (2 surveys perpendicular to each other).

With nadir imagery (I guess that's what you were collecting so far) it is very difficult (impossible) to get clean textures on subvertical objects such as walls/buildings because they are not properly visible in the imagery.

Also use a high(er) image overlap when dealing with complex geometries (80-90%).

Regards,
SAV

cadm8

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Re: Texture smoothness
« Reply #3 on: September 19, 2017, 05:07:56 PM »
actually there was oblique imagery involved both in grid collection, as well as a downward spiral, as you can see in the attachment. I guess though that there should be a better survey grid and more overlap, maybe more than 80%...

stihl

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Re: Texture smoothness
« Reply #4 on: September 19, 2017, 05:54:19 PM »
Try using the Adaptive Orthophoto when building the Texture instead of the default Generic mode.

SAV

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Re: Texture smoothness
« Reply #5 on: September 19, 2017, 07:01:49 PM »
Hi cadm8,

'Grid survey' with oblique imagery should lead to better results. However, you should also get OK results with your survey design.

Have you checked the image quality? Blurry/low quality images might explain some of your texture problems.

Additionally, have you cleaned up your sparse point cloud using EDIT > GRADUAL SELECTION before computing the dense point cloud? You should get rid of all tie points with high reprojection error and high reconstruction uncertainty. Also use aggressive depth filtering for the dense point cloud.

Last but not least, disable 'duplicate' images which have been taken at the same location. I've experienced some issues in the past when pictures were very very close to each other and basically had the same orientation.

I hope that helps and improves your results #fingerscrossed

Regards,
SAV

actually there was oblique imagery involved both in grid collection, as well as a downward spiral, as you can see in the attachment. I guess though that there should be a better survey grid and more overlap, maybe more than 80%...